recursiveloader: Support creating sub-Manifest

2 files changed, 27 insertions, 1 deletions

diff --git a/gemato/recursiveloader.py b/gemato/recursiveloader.py
index 65dd424..a52f333 100644
--- a/gemato/recursiveloader.py
+++ b/gemato/recursiveloader.py
@@ -519,7 +519,9 @@ class ManifestRecursiveLoader(object):
         self.updated_manifests -= set(gemato.compression
                 .get_potential_compressed_names('Manifest'))
         # at this point, the list should be empty
-        assert not self.updated_manifests
+        assert not self.updated_manifests, (
+                "Unlinked but updated Manifests: {}".format(
+                    self.updated_manifests))
 
     def update_entry_for_path(self, path, new_entry_type='DATA',
             hashes=None):
@@ -931,3 +933,14 @@ class ManifestRecursiveLoader(object):
 
             self.loaded_manifests[mpath].entries.remove(fe)
             self.updated_manifests.add(mpath)
+
+    def create_manifest(self, path):
+        """
+        Create a new empty sub-Manifest instance at relative path @path.
+        The file will not be written until save_manifests(). No MANIFEST
+        entry for the file will be created.
+
+        Returns the new ManifestFile instance.
+        """
+
+        return self.load_manifest(path, allow_create=True)
diff --git a/tests/test_recursiveloader.py b/tests/test_recursiveloader.py
index 366522a..c115763 100644
--- a/tests/test_recursiveloader.py
+++ b/tests/test_recursiveloader.py
@@ -2649,6 +2649,19 @@ MANIFEST z/Manifest 0 MD5 d41d8cd98f00b204e9800998ecf8427e
         m.save_manifests()
         m.assert_directory_verifies()
 
+    def test_create_manifest(self):
+        m = gemato.recursiveloader.ManifestRecursiveLoader(
+            os.path.join(self.dir, 'Manifest'))
+        self.assertIsNotNone(m.create_manifest('a/y/Manifest'))
+        self.assertFalse(os.path.exists(os.path.join(
+            self.dir, 'a/y/Manifest')))
+        m.loaded_manifests['Manifest'].entries.append(
+                gemato.manifest.ManifestEntryMANIFEST(
+                    'a/y/Manifest', 0, {}))
+        m.save_manifests()
+        self.assertTrue(os.path.exists(os.path.join(
+            self.dir, 'a/y/Manifest')))
+
 
 class AddingToMultipleManifestsTest(TempDirTestCase):
     """